Objective To explore the pulmonary arterial pressure level in patients with predialysis chronic kidney disease ( CKD) and its relationship to cardiac structure and function. Methods 397 patients with predialysis CKD and 50 healthy subjects were enrolled. Cardiac structure was evaluated by Doppler echocardiography. Glomerular filtration rate ( GFR ) were assessed by radiant 99mTc-DTPA.Differences of PAP, BNP, LA, IVST, LVDd, LVDs, LVEF, LVMI and the correlation of PAP with cardiac structure and function were examined. Results The PAP level in the predialysis CKD patients was much higher than that in the healthy subjects [ ( 33. 13 ±9. 00) mm Hg vs. ( 29. 43 ±3. 71) mmHg, P lt;0. 01] .18. 9% of the CKD patients were complicated with pulmonary hypertension. PAP was higher in the CKD patients in stages 4-5 than those CKD patients in stages 1-3 [ ( 35. 90 ±9. 34) mmHg vs. ( 32. 08 ±8. 62)mmHg, P lt;0. 01) ] , so as to the prevalene of pulmonary hypertension ( 21. 60% vs. 13. 47% , P lt;0. 01) .Compared with the healthy, the level of lnBNP [ ( 3. 59 ±1. 63) pg/mL vs. ( 2. 88 ±1. 51) pg/mL, P lt;0. 01] , LA [ ( 40. 42 ±6. 77) mmvs. ( 36. 75 ±4. 94) mm, P lt; 0. 01) ] , LVPW [ ( 9. 55 ±1. 96) mm vs.( 8. 54 ±0. 88) mm, P lt; 0. 01) ] , IVST [ ( 9. 76 ±1. 75) mm vs. ( 8. 71 ±0. 90) mm, P lt; 0. 01) ] , LVMI[ ( 105. 61 ±36. 47) g/m2 vs. ( 87. 41 ±17. 08) g/m2 , P lt; 0. 01) ] were all much higher. There was a negative correlation between PAP and GFR( r = - 0. 461, P lt;0. 01) , and positive correlations between PAP and LA ( r=0. 491, P lt; 0. 01) , LVPW ( r =0. 298, P lt;0. 01) , IVST ( r = 0. 613, P lt;0. 01) , lnBNP ( r =0. 536, P lt;0. 01) , LVMI ( r = 0. 382, P lt;0. 01) . LVMI and lnBNP were both independent risk factors of PAP. The regression equation: y = 16. 447 + 0. 105x1 + 1. 724x2 ( F = 23. 482, P = 0. 000) , y: PAP( mm Hg) , x1 : LVMI( g/m2 ) , x2 : lnBNP( pg/mL) . Conclusions Pulmonary hypertension is a common morbidity of predialysis CKD patients, and deteriorates with degression of renal function. PAP is related to indexes of cardiac structure ( LVMI, LA, LVPW, IVST) and index of cardiac function ( lnBNP) . LnBNP and LVMI are independent risk factors of PAP.